Apparatus and methods for forming and securing gastrointestinal tissue folds

ABSTRACT

Apparatus and methods are provided for forming a gastrointestinal tissue fold by engaging tissue at a first tissue contact point, moving the first tissue contact point from a position initially distal to a second tissue contact point to a position proximal of the second contact point to form a tissue fold, and extending an anchor assembly through the tissue fold near the second tissue contact point. Adjustable anchor assemblies, as well as anchor delivery systems, are also provided.

REFERENCE TO RELATED APPLICATIONS

This application claims priority from U.S. provisional patentapplication Ser. No. 60/500,627, filed Sep. 5, 2003, and is aContinuation-In-Part of U.S. patent application Ser. No. 10/612,170,filed Jul. 1, 2003, as well as U.S. patent application Ser. No.10/639,162, filed Aug. 11, 2003, both of which claim priority from U.S.provisional patent application Ser. No. 60/433,065, filed Dec. 11, 2002,all of which are incorporated herein by reference in their entirety.

FIELD OF THE INVENTION

The present invention relates to methods and apparatus forintraluminally forming and securing gastrointestinal (“GI”) tissuefolds. More particularly, the present invention relates to methods andapparatus for reducing the effective cross-sectional area of agastrointestinal lumen.

BACKGROUND OF THE INVENTION

Morbid obesity is a serious medical condition pervasive in the UnitedStates and other countries. Its complications include hypertension,diabetes, coronary artery disease, stroke, congestive heart failure,multiple orthopedic problems and pulmonary insufficiency with markedlydecreased life expectancy.

Several surgical techniques have been developed to treat morbid obesity,e.g., bypassing an absorptive surface of the small intestine, orreducing the stomach size. These procedures are difficult to perform inmorbidly obese patients because it is often difficult to gain access tothe digestive organs. In particular, the layers of fat encountered inmorbidly obese patients make difficult direct exposure of the digestiveorgans with a wound retractor, and standard laparoscopic trocars may beof inadequate length.

In addition, previously known open surgical procedures may presentnumerous life-threatening postoperative complications, and may cause atypical diarrhea, electrolytic imbalance, unpredictable weight loss andreflux of nutritious chyme proximal to the site of the anastamosis.Further, the sutures or staples that are often used in these surgicalprocedures may require extensive training by the clinician to achievecompetent use, and may concentrate significant force over a smallsurface area of the tissue, thereby potentially causing the suture orstaple to tear through the tissue.

The gastrointestinal lumen includes four tissue layers, wherein themucosa layer is the top tissue layer followed by connective tissue, themuscularis layer and the serosa layer. One problem with conventionalgastrointestinal reduction systems is that the anchors (or staples) mustengage at least the muscularis tissue layer in order to provide a properfoundation. In other words, the mucosa and connective tissue layerstypically are not strong enough to sustain the tensile loads imposed bynormal movement of the stomach wall during ingestion and processing offood. In particular, these layers tend to stretch elastically ratherthan firmly hold the anchors (or staples) in position, and accordingly,the more rigid muscularis and/or serosa layer must be engaged. Thisproblem of capturing the muscularis or serosa layers becomesparticularly acute where it is desired to place an anchor or otherapparatus transesophageally rather than intraoperatively, since caremust be taken in piercing the tough stomach wall not to inadvertentlypuncture adjacent tissue or organs.

In view of the aforementioned limitations, it would be desirable toprovide methods and apparatus for forming gastrointestinal tissue foldsthat achieve gastric reduction by reconfiguring the GI lumen of apatient.

It would be desirable to provide methods and apparatus for forminggastrointestinal tissue folds using anchors that can be reconfiguredfrom a reduced delivery profile to an expanded deployed profile.

It also would be desirable to provide methods and apparatus for forminggastrointestinal tissue folds, wherein an anchor assembly is extendedacross stomach folds that include the muscularis and serosa tissuelayers.

It further would be desirable to provide methods and apparatus forforming gastrointestinal tissue folds, wherein the anchor assembly isdeployed in a manner that reduces a possibility of injuring neighboringorgans.

It still further would be desirable to provide methods and apparatus forforming gastrointestinal tissue folds, wherein reduced training of aclinician is required to achieve competent use of the anchor assembly.

SUMMARY OF THE INVENTION

In view of the foregoing, it is an object of the present invention toprovide methods and apparatus for forming gastrointestinal tissue foldsthat achieve gastric reduction by reconfiguring the GI lumen of apatient.

It is another object of the present invention to provide methods andapparatus for forming gastrointestinal tissue folds using anchors thatcan be reconfigured from a reduced delivery profile to an expandeddeployed profile.

It is an additional object of this invention to provide methods andapparatus for forming gastrointestinal tissue folds in which an anchorassembly is extended across stomach folds that include the muscularisand serosa tissue layers.

It is a further object of the present invention to provide methods andapparatus for forming gastrointestinal tissue folds, wherein the anchorassembly is deployed in a manner that reduces a possibility of injuringneighboring organs.

It is yet another object to provide methods and apparatus for forminggastrointestinal tissue folds, wherein reduced training of a clinicianis required to achieve competent use of the anchor assembly.

These and other objects of the present invention are accomplished byproviding a catheter configured for advancement into a patient'sgastrointestinal lumen to form a gastrointestinal tissue fold. In onepreferred embodiment, the catheter has a distal region including atissue grabbing assembly adapted to engage and stretch a portion of thetissue wall of the GI lumen at a first tissue contact point. A secondtissue contact point is then established with the tissue wall at alocation initially proximal of, or in line with, the first tissuecontact point. The tissue engaged by the tissue grabbing assembly thenis moved to a position proximal of the second tissue contact point toform a tissue fold, and an anchor assembly may be delivered across thetissue fold. Preferably, delivery of the anchor assembly across thetissue fold includes delivering the anchor assembly across themuscularis and serosa layers of the tissue wall.

In a preferred embodiment, the tissue grabbing assembly is carried on afirst flexible tube associated with the distal region of the catheter,and the anchor assembly is delivered by an anchor delivery systemdisposed within a second flexible tube associated with the distal regionof the catheter. The tissue grabbing assembly may comprise any of anumber of mechanisms configured to engage the tissue wall, including apair of jaws configured to move between open and closed positions, aplurality of linearly translating barbs, or one or more needles orhooks. The first tissue contact point may be moved from a tissueengagement position distal to, or in line with, the second tissuecontact point, to the tissue folding position by any of a number ofmechanisms, including a hinge assembly or a treadmill assembly.

More preferably, the distal region of the catheter includes a bendablesection that permits the first tissue contact point to be positionedrelative to the second tissue contact point so that the tissue fold isoriented substantially perpendicular to the anchor delivery system. Inthis manner, the anchor delivery system, when deployed, pierces thetissue fold and exits into the interior of the GI lumen, rather than theexterior of the tissue wall, thereby reducing a risk of injury toadjacent organs.

The anchor assembly delivery system of the present invention preferablycomprises a needle or obturator adapted to pierce the tissue fold anddeliver an anchor assembly. In one preferred embodiment, the anchorassembly comprises a pair of rod-like anchors that are delivered througha needle in a reduced delivery profile, wherein the longitudinal axis ofthe rods is substantially parallel to the longitudinal axis of theneedle. Once ejected from the needle, the rods rotate about 90 degreesto engage the tissue. In other embodiments, the anchor assembly maycomprise anchors of various shaped delivered, for example, over theexterior of an obturator.

Methods of using the apparatus of the present invention also areprovided.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects and advantages of the present invention willbe apparent upon consideration of the following detailed description,taken in conjunction with the accompanying drawings, in which likereference characters refer to like parts throughout, and in which:

FIGS. 1A and 1B are, respectively, a side view and detail view ofapparatus of the present invention for forming a gastrointestinal foldin accordance with the principles of the present invention;

FIGS. 2A and 2B are side-sectional views of a tissue grabbing assemblysuitable for use with the apparatus of FIG. 1;

FIGS. 3A-3E are side views illustrating a method of using the apparatusof FIG. 1 to form a gastrointestinal fold;

FIGS. 4A-4C are side-sectional views of an anchor assembly and deliverysystem suitable for use with apparatus of the present invention;

FIGS. 5A and 5B are side-sectional views of another anchor assemblysuitable for use with apparatus of the present invention;

FIGS. 6A and 6B are side-sectional views of another alternative anchorassembly suitable for use with apparatus of the present invention;

FIGS. 7A-7C are, respectively, a schematic side-sectional view of aunidirectionally adjustable anchor assembly suitable for use withapparatus of the present invention, schematic side-sectional views ofalternative techniques for fixing the distal anchor of the assembly, anda cross-sectional view of the proximal anchor taken along section lineA-A of FIG. 7A;

FIGS. 8A and 8B are schematic cross-sectional views illustrating theunidirectional adjustment capability of the anchor assembly of FIG. 7;

FIGS. 9A-9C are schematic cross-sectional views of alternativeembodiments of the proximal anchor of the anchor assembly of FIG. 7;

FIGS. 10A and 10B are schematic cross-sectional views of an alternativeunidirectionally adjustable anchor assembly suitable for use withapparatus of the present invention;

FIGS. 11A-11C are, respectively, a schematic side-view of anotheralternative unidirectionally adjustable anchor assembly suitable for usewith the present invention, and cross-sectional views of the same takenalong section line B-B of FIG. 11A;

FIG. 12 is a schematic cross-sectional view of an alternativeunidirectionally adjustable anchor assembly comprising pivoting paddles;

FIG. 13 is a schematic cross-sectional view of an alternativeunidirectionally adjustable anchor assembly comprising spring material;

FIGS. 14A-14B are schematic side-sectional views of alternativeunidirectionally adjustable anchor assemblies comprising one-way valves;

FIGS. 15A-15C are side-sectional and detail views of alternativeunidirectionally adjustable anchor assemblies comprising slipknots;

FIGS. 16A-16C are, respectively, a schematic side-sectional view of abi-directionally adjustable anchor assembly comprising a lockingmechanism, and cross-sectional views of the same taken along sectionline C-C of FIG. 16A;

FIGS. 17A-17D are perspective views of alternative anchors suitable foruse with the anchor assemblies of the present invention;

FIGS. 18A-18D are side views of alternative apparatus for forming agastrointestinal fold;

FIG. 19 is a cross-sectional view of the apparatus of FIGS. 18A-18D;

FIGS. 20A-20D are side views of further alternative apparatus forforming a gastrointestinal tissue fold in accordance with the principlesof the present invention;

FIGS. 21A-21G are schematic side-sectional views of an anchor deliverysystem adapted for use with the adjustable anchor assemblies of FIGS.7-17, illustrating a method of delivering the unidirectionallyadjustable anchor assembly of FIG. 7 across a tissue fold;

FIGS. 22A and 22B are, respectively, a schematic side-view, partially insection, and an end-view of an alternative anchor delivery systemadapted for use with the adjustable anchor assemblies of FIGS. 7-17,wherein the proximal anchor is disposed within a separate delivery tube;

FIG. 23 is a schematic side-sectional view of an alternative anchordelivery system adapted for use with the adjustable anchor assemblies ofFIGS. 7-17, wherein both the proximal and distal anchors are loadedwithin the needle; and

FIG. 24 is a schematic side-sectional view of an alternative embodimentof the anchor delivery system of FIG. 23 comprising motion limitationapparatus.

DETAILED DESCRIPTION OF THE INVENTION

In accordance with the principles of the present invention, methods andapparatus are provided for intraluminally forming and securinggastrointestinal (“GI”) tissue folds, for example, to reduce theeffective cross-sectional area of a GI lumen. These methods andapparatus may be used to treat obesity by approximating the walls of agastrointestinal lumen to narrow the lumen, thus reducing the area forabsorption in the stomach or intestines. More particularly, the presentinvention involves endoscopic apparatus that engages a tissue wall ofthe gastrointestinal lumen, creates a tissue fold and disposes an anchorassembly through the tissue fold. Preferably, the anchor assembly isdisposed through the muscularis and/or serosa layers of thegastrointestinal lumen. In operation, a distal tip of the probe engagesthe tissue and then moves the engaged tissue to a proximal positionrelative to the catheter tip, thereby providing a substantially uniformplication of predetermined size.

Formation of a tissue fold preferably is accomplished using two tissuecontact points that are separated by a linear or curvilinear distance,wherein the separation distance between the tissue contact pointsaffects the length and/or depth of the fold. In operation, a tissuegrabbing assembly engages the tissue wall in its normal state (i.e.,non-folded and substantially flat), thus providing a first tissuecontact point. The first tissue contact point then is moved to aposition proximal of a second tissue contact point to form the tissuefold. An anchor assembly then may be extended across the tissue fold atthe second tissue contact point.

More preferably, the first tissue contact point is used to engage andthen stretch or rotate the tissue wall over the second tissue contactpoint to form the tissue fold. The tissue fold is then articulated to aposition so that a portion of the tissue fold overlies the second tissuecontact point at an orientation that is substantially normal to thetissue fold. An anchor then is delivered across the tissue fold at ornear the second tissue contact point.

Referring to FIG. 1, apparatus 10 of the present invention comprisestorqueable catheter 11 having distal region 12 from which first andsecond interconnected flexible tubes 13 and 14 extend, and proximalregion 15 having handle 16 and actuator 17. Catheter 11 is configuredfor insertion through a patient's mouth and esophagus into thegastrointestinal lumen. Tissue grabbing assembly 18 is disposed on thedistal end of flexible tube 13, and is coupled to actuator 17 viacontrol wire 19 that extends through flexible tube 13.

As better illustrated in FIG. 1B, flexible tubes 13 and 14 are connectedvia hinge assembly 20 that comprises link 21 attached to flexible tube13 at pivot point 22 and attached to flexible tube 14 at pivot point 23.Hinge assembly 20 prevents tissue grabbing assembly 18 from moving morethan a predetermined distance relative to distal end 24 of flexible tube14.

Still referring to FIG. 1B, flexible tubes 13 and 14 preferably includebendable sections 25 and 26, respectively, that comprise a plurality ofthrough-wall slots 27 to enhance flexibility of the tube. Preferably,flexible tubes 13 and 14 are made from stainless steel with an etched orlaser-cut slot pattern. More preferably, the slot pattern is asinusoidal repeating pattern of slots perpendicular to the longitudinalaxis of tubes 13 and 14.

Referring to FIGS. 2A and 2B, tissue grabbing assembly 18 comprises pairof jaws 28 a, 28 b arranged to rotate about pivot point 29 between anopen configuration (FIG. 2A) and a closed configuration (FIG. 2B).Control wire 19 is coupled via pivot point 30 to arms 31 a and 31 b.Arms 31 a and 31 b are in turn pivotally coupled to jaws 28 a and 28 b,respectively, at pivot points 32 a and 32 b. Each of jaws 28 a and 28 bpreferably includes sharpened teeth 33 disposed near its distal ends tofacilitate grasping of the tissue wall of the GI lumen.

Control wire 19 is coupled to actuator 17 of handle 16 so thattranslation of the wire within flexible tube 13 causes the jaws to openor close. In particular, urging control wire distally (as indicated byarrow A in FIG. 2A) moves pivot point 30 distally, thereby forcing thejaws to open. Urging control wire 19 proximally (as indicated by arrow Bin FIG. 2B) moves pivot point 30 proximally, thereby forcing the jaws toclose together. In alternative embodiments, tissue grabbing assembly 18may comprise a grappling hook or fork, or plurality of needles coupledto the distal end of flexible tube 13.

Flexible tube 14 is affixed to and immovable within catheter 11, whileflexible tube 13 is coupled to catheter 11 only via hinge 20.Accordingly, when control wire 19 is extended in the distal direction,flexible tube 13 is carried in the distal direction. When control wire19 is retracted in the proximal direction, flexible tube remainsstationary until jaws 28 a and 28 b close together, after which furtherretraction of control wire 19 by moving actuator 17 causes flexible tube13 to buckle in bendable region 25, as described hereinafter.

Referring now to FIGS. 1 and 3A-3E, operation of apparatus 10 isdescribed to create a tissue fold in a tissue wall of a GI lumen. InFIG. 3A, distal region 12 of catheter 11 is positioned within apatient's GI lumen transesophageally, and jaws 28 a and 28 b of tissuegrabbing assembly 18 are opened by moving actuator 17 to the distal-mostposition on handle 16. As depicted in FIG. 3B, actuator 17 may then bemoved proximally until the jaws of tissue grabbing assembly 18 engage aportion of tissue wall W at contact point P1.

Referring to FIG. 3C, after the tissue wall has been engaged at contactpoint P1, flexible tube 13 is urged proximally within catheter 11 byfurther proximal retraction of control wire 19 to stretch tissue wall Wand create tissue fold F. During this movement of flexible tube 13, link21 of hinge assembly 20 causes tissue grabbing assembly 18 to move froma position distal to distal end 24 of flexible tube 14, to a positionproximal of distal end 24 of flexible tube 14. Bendable sections 25 and26 of flexible tubes 13 and 14, respectively, accommodate any lateralmotion caused by operation of hinge assembly 20. Advantageously,formation of fold F facilitates the penetration of the tissue wall by aneedle and subsequent delivery of an anchor assembly, as describedhereinafter.

Referring to FIG. 3D, additional proximal movement of actuator 17 causesflexible tubes 13 and 14 to buckle at bendable sections 25 and 26. Hingeassembly 20 transmits force applied to flexible tube 13 via control wire19 and actuator 17 to the distal tip 24. Preferably, flexible tube 14 isconfigured so that distal tip 24 contacts, and is substantiallyperpendicular, to tissue fold F at contact point P2. As illustrated inFIG. 3E, once tissue fold F is stretched across distal tip 24 offlexible tube 14, sharpened needle or obturator 34 may be extended fromdistal tip 24 of flexible tube 14 to pierce all four layers of thetissue wall W. Sharpened needle or obturator 34 is inserted via inlet 35to flexible tube 14 on handle 16 (see FIG. 1A).

As discussed above, the GI lumen comprises an inner mucosal layer,connective tissue, the muscularis layer and the serosa layer. To obtaina durable purchase, e.g., in performing a stomach reduction procedure,the staples or anchors used to achieve reduction of the GI lumen mustengage at least the muscularis tissue layer, and more preferably, theserosa layer as well. Advantageously, stretching of tissue fold F acrossdistal tip 24 permits an anchor to be ejected through both themuscularis and serosa layers, thus enabling durable gastrointestinaltissue approximation.

As depicted in FIG. 3E, after tissue fold F is stretched across distaltip 24 of flexible tube 14 to form contact point P2 with tissue wall W,needle 34 may be extended from distal tip 24 and through tissue fold F.Because needle 34 penetrates the tissue wall twice, it exits within thegastrointestinal lumen, thus reducing the potential for injury tosurrounding organs. Once the needle has penetrated tissue fold F, ananchor assembly is ejected through distal tip 24 as describedhereinbelow.

With respect to FIGS. 4A-4C, a first embodiment of an anchor assemblysuitable for use with the apparatus of the present invention isdescribed. Anchor assembly 36 comprises T-anchor assembly having distalrod 38 a and proximal rod 38 b connected by suture 39. The preciseshape, size and materials of the anchors may vary for individualapplications. In addition, the suture material also may vary forindividual applications. By way of example, the suture material mayconsist of monofilament wire, multifilament wire or any otherconventional suture material. Alternatively, suture 39 may compriseelastic material, e.g. a rubber band, to facilitate adjustment of thedistance between the proximal and distal rods. Suture 39 extends througha pair of through-holes 40 in each rod, thereby forming a loop.Alternatively, suture 39 may be attached to the rods via an eyelet orusing a suitable adhesive. Preferably, through-holes 40 are located nearthe center of the rods 38 a and 38 b.

Referring to FIG. 4B, rods 38 a and 38 b may be delivered through needle34 (see FIG. 3E) using push rod 42. Push rod 42 is adapted to freelytranslate through flexible tube 14 and needle 34. Push rod 42 ispreferably flexible, so that it may slide through bendable section 26 offlexible tube 14. In addition, push rod 42 may include notch 43 near itsdistal end to facilitate grasping and tensioning suture 39 after anchordelivery.

During anchor delivery, the longitudinal axis of distal rod 38 a issubstantially parallel to the longitudinal axis of needle 34. However,once distal rod 38 a is ejected from needle 34, suture tension inducesthe rod to rotate approximately 90 degrees about its longitudinal axis,so that its longitudinal axis is substantially perpendicular to thelongitudinal axis of needle 35. This rotation of distal rod 38 aprevents it from being pulled back through tissue wall W.

Referring to FIG. 4C, once rod 38 a is ejected on the distal side offold F, needle 35 is retracted and push rod 42 is used to eject rod 38 bon the proximal side of tissue fold F. Like distal rod 38 a, tension inthe suture causes proximal rod 38 b to rotate about 90 degrees once itis ejected from the needle. Notch 43 in push rod 42 then may be employedto tighten suture 39 by any of a variety of mechanisms. Alternatively,suture 39 may comprise an elastic material that dynamically tightens therods against tissue fold F.

Referring now to FIG. 5A, according to other embodiments, the anchorassembly comprises a T-anchor assembly suitable to be disposed overobturator 50. More particularly, distal rod 38 a includes through-hole51 dimensioned for the passage of obturator tip 52, and obturator 50 istranslatably inserted through flexible tube 14 via inlet 35 of handle 16(see FIG. 1A). Proximal rod 38 b may be a solid rod that does notinclude a through-hole for passage of obturator 50. Alternatively,proximal rod 38 b may include a through-hole for the passage of theobturator. Preferably, obturator tip 52 is sharpened to facilitatetissue penetration.

With respect to FIG. 5B, once rod 38 a is ejected on the distal side offold F, it rotates into a position substantially parallel to tissue wallW and perpendicular to the longitudinal axis of the obturator. Obturator50 then is retracted and proximal rod 38 b is ejected from flexible tube14. More particularly, when flexible tube 14 is retracted from tissuewall W, proximal rod 38 b is pulled through distal tip 24. Proximal rod38 b then rotates substantially 90 degrees as it is ejected fromflexible tube 14 so that rod 38 b is urged against tissue wall W.

Referring to FIG. 6A, according to further embodiments, anchor assembly55 comprises a T-anchor assembly similar to the embodiment depicted inFIG. 4A. However, anchor assembly 55 includes fine wire tether 56 thatmay be twisted to maintain the tension between rods 38 a and 38 b.

With respect to FIG. 6B, a method of delivering anchor assembly 55 isdescribed. Initially, distal rod 38 a is delivered across both tissuewalls using needle 34. The needle then is retracted to release distalrod 38 a so that it engages the tissue wall. Next, needle 34 isretracted to release proximal rod 38 b, so that it too rotates intoengagement with the tissue wall. A proximal portion of the wire tetheris captured by notch 43 of push rod 42 (see FIG. 4B), and the push rodis rotated to cause proximal rod 38 b to clamp down on the tissue fold.Because wire tether 56 is twisted by rotation of push rod 42, itmaintains the desired force on the tissue walls.

Referring now to FIG. 7, a unidirectionally adjustable anchor assemblysuitable for use with apparatus of the present invention is described.Anchor assembly 60 comprises distal anchor 62 and unidirectionallyadjustable proximal anchor 64, which are connected by suture 39. Distalanchor 62 is translationally fixed with respect to suture 39. Suchfixation may be achieved in a variety of ways. For example, as seen inFIG. 7A, distal anchor 62 may comprise a pair of through-holes 63,located near the center of anchor 62 and through which suture 39 isthreaded and tied off at knot 65.

FIG. 7B provides alternative techniques for fixing the distal anchor. Asseen in FIG. 7B(i), distal anchor 62 may comprise hollow tube T havingopening O. A distal end of suture 39 is passed through opening O andformed into knot K, which is dimensioned such that it cannot passthrough opening O, thereby fixing the distal anchor with respect to thesuture. In order to facilitate formation of knot K, distal anchor 62optionally may comprise distal opening DO, which is dimensioned suchthat knot K may pass therethrough. The distal end of suture 39 may bepassed through distal opening DO, knotted, and then pulled back withinhollow tube T of anchor 62 until it catches at opening O.

A drawback of the fixation technique described with respect to FIG.7B(i) is a risk of suture 39 being torn or cut due to rubbing againstopening O. In FIG. 7B(ii), hollow tube T comprises first end E to whichis connected wire loop L, which may be formed, for example from anickel-titanium alloy (“Nitinol”). Suture 39 passes through the wireloop before terminating at knot K. Knot K is dimensioned such that itcannot pass back through the wire loop. Wire loop L directs suture 39through opening O, thereby reducing rubbing of the suture against theopening and reducing a risk of tearing or cutting of suture 39.

FIG. 7B(iii) provides yet another alternative technique for fixing thedistal anchor with respect to the suture. Distal anchor 62 againcomprises hollow tube T having opening O. Rod R is disposed within tubeT, and the ends of the tube may be either closed or crimped to rod R,such that the rod is maintained within the tube. The distal end ofsuture 39 is threaded through opening O, around rod R, and back outopening O. The suture is then knotted at knot K, thereby fixing distalanchor 62 with respect to suture 39.

In addition to the techniques shown in FIGS. 7A and 7B, suture 39alternatively may be fixed with respect to anchor 62 by other means, forexample, via a knotted eyelet or via a suitable adhesive. Additionaltechniques will be apparent to those of skill in the art. While anchor62 is illustratively shown as a rod- or T-type anchor, any of a varietyof anchors, per se known, may be used as distal anchor 62. Exemplaryanchors are described in co-pending U.S. patent application Ser. No.10/612,170, filed Jul. 1, 2003, which is incorporated herein byreference in its entirety. Additional anchors are described hereinbelowwith respect to FIG. 17.

Referring again to FIG. 7A, adjustable proximal anchor 64 comprisesouter cylinder 66 having first end 67 a and second end 67 b, as well asfirst opening 68 a and second opening 68 b. First and second openings 68are preferably disposed near the center of cylinder 66 and approximately180° apart. Anchor 64 further comprises first flexible rod 70 a andsecond flexible rod 70 b, both of which are disposed within outercylinder 66 and coupled to first and second ends 67 of cylinder 66. Rods70 may be formed, for example, from Nitinol or from a polymer, and maybe separated from one another by small gap G. As with the previousanchor assemblies, the precise shape, size and materials of the anchorsand suture may vary as required for specific applications.

As best seen in FIG. 7C, suture 39 passes from distal anchor 62 throughfirst opening 68 a of proximal anchor 64, around second flexible rod 70b, around first flexible rod 70 a, between rods 70 a and 70 b, and outthrough second opening 68 b. This suture winding provides aunidirectional adjustment capability that allows a length L of suture 39disposed between distal anchor 62 and proximal anchor 64 to beshortened. However, the suture winding precludes an increase in lengthL. FIG. 8 illustrate the mechanism of this unidirectional adjustmentcapability in greater detail. Optionally, suture 39 may be tied offproximal of anchor 64 at knot 69, thereby forming a proximal loop ofsuture to facilitate deployment and/or adjustment of anchor assembly 60.

In FIG. 8A, a proximally-directed force F₁ is applied to suture 39proximal of adjustable anchor 64, while anchor 64 is held stationary oris advanced distally. A portion of force F₁ is transferred throughsuture 39 to second flexible rod 70 b, which causes rod 70 b to bow,thereby increasing gap G and allowing suture 39 to freely pass betweenrods 70 a and 70 b and through proximal anchor 64, facilitatingunidirectional adjustment. When anchor 64 is held stationary whilesuture 39 is retracted proximally, distal anchor 62 retracts proximallytowards anchor 64. Alternatively, when anchor 64 is advanced distallywhile suture 39 is retracted proximally, distal anchor 62 either remainsstationary or retracts proximally towards proximal anchor 64, dependingupon a degree of distal advancement of proximal anchor 64. Regardless,length L of suture 39 disposed between anchors 62 and 64 is decreased,thereby unidirectionally adjusting a distance between the anchors.

In FIG. 8B, a distally-directed force F₂ is applied to suture 39 distalof adjustable anchor 64. Force F₂ may be applied, for example, by tissuecompressed between anchors 62 and 64. Compressed tissue stores energy ina manner similar to a compression spring and seeks to push anchors 62and 64 apart after unidirectional tightening. Force F₂ causes the loopof suture 39 around first and second rods 70 to tighten, thereby bowingboth rods inward and closing gap G such that suture 39 is frictionlocked between first and second flexible rods 70. In this manner, thelength L of suture between anchors 62 and 64 may be selectivelydecreased but cannot be increased.

As will be apparent to those of skill in the art, the magnitude of forcerequired to unidirectionally adjust length L may be altered in a varietyof ways. For example, a length, flexibility or diameter of rods 70 maybe altered. Likewise, the elasticity or diameter of suture 39 may bealtered. Initial gap G may be increased or decreased. Furtherstill, thematerials used to form rods 70 and suture 39 may be changed to altermaterial properties, such as coefficients of friction, and/or rods 70 orsuture 39 may comprise a lubricious coating. Additional methods forvarying the magnitude of force, a few of which are described hereinbelowwith respect to FIG. 9, will be apparent in view of this disclosure andare included in the present invention.

Referring now to FIG. 9, alternative anchors 64 are described. In FIG.9A, flexible rods 70 of proximal adjustable anchor 64′ are rotated withrespect to openings 68 (or vice versa). When utilizing the suturewinding described in FIGS. 7 and 8, rotation of rods 70 up to 180°clockwise progressively increases friction when force is applied toanchors 62 and 64. The magnitude of the friction lock is increased whenforce is applied in the manner described with respect to FIG. 8B.However, friction is also increased when unidirectionally adjusting thelength of suture between the proximal and distal anchors by applyingforce in the manner described with respect to FIG. 8A. Rotation of rods70 more than about 180° clockwise would cause anchor 64′ to frictionlock regardless of which direction force were applied to suture 39,thereby negating the unidirectional adjustment capability.Counterclockwise rotation of rods 70 with respect to openings 68 wouldinitially reduce friction during force application to suture 39 ineither direction. It is expected that counterclockwise rotation inexcess of about 90° would eliminate the friction lock described in FIG.8B and allow bidirectional adjustment. Continued counterclockwiserotation beyond about 450° would reverse the directions of friction lockand unidirectional adjustment, while counterclockwise rotation beyondabout 720° would result in friction lock regardless of which directionforce were applied to suture 39.

As discussed previously, openings 68 of cylinder 66 of anchor 64 arepreferably disposed approximately 180° apart from one another. However,in order to increase the friction lock force without significantlyincreasing friction during unidirectional adjustment, first opening 68 amay be rotated counterclockwise with respect to second opening 68 b (orvice versa), as seen with anchor 64″ of FIG. 9B. In this manner, firstopening 68 a is no longer in line with rods 70, while second opening 68b remains in line with rods 70. When force F₁ is applied to anchor 64″,second flexible rod 70 b is able to bow outward and increase gap G,thereby facilitating unidirectional adjustment. Likewise, when force F₂is applied to the anchor, gap G is closed more tightly upon suture 39,thereby increasing the friction lock force. If first opening 68 aalternatively were rotated clockwise with respect to the second opening,it is expected that the friction lock force would be decreased.

In FIG. 9C, proximal adjustable anchor 64′″ comprises an alternativesuture winding. Suture 39 passes from distal anchor 62 through firstopening 68 a of anchor 64′″, around second flexible rod 70 b, aroundfirst flexible rod 70 a, back around second flexible rod 70 b, betweenrods 70 a and 70 b, and out through second opening 68 b. As with thesuture winding described with respect to anchor 64 of FIGS. 7 and 8, thesuture winding illustrated in FIG. 9C provides a unidirectionaladjustment capability that allows a length L of suture 39 disposedbetween distal anchor 62 and proximal anchor 64′″ to be shortened.However, this suture winding precludes an increase in length L.Additional unidirectionally adjustable suture windings will be apparentto those of skill in the art.

With reference to FIG. 10, an alternative unidirectionally adjustableanchor comprising three rods is described. Anchor assembly 80 comprisesdistal anchor 62 and proximal anchor 82. Unidirectionally adjustableproximal anchor 82 comprises outer cylinder 84 having first end 85 a andsecond end 85 b (not shown), as well as first opening 86 a and secondopening 86 b. First and second openings 86 are preferably disposed nearthe center of cylinder 84 and approximately 180° apart. Anchor 82further comprises first flexible rod 88 a, second flexible rod 88 b andthird flexible rod 88 c, all of which are disposed within outer cylinder66 and coupled to first and second ends 85 of cylinder 64. Rods 88 areseparated from one another by gaps G₁ and G₂.

Suture 39 passes from distal anchor 62 through first opening 86 a ofproximal anchor 82, around first rod 88 a, between first rod 88 a andsecond rod 88 b, between second rod 88 b and third rod 88 c, aroundthird rod 88 c, back to and around first rod 88 a, and out throughsecond opening 86 b. As seen in FIG. 10A, when force F₁ is applied tosuture 39, gaps G₁ and G₂ remain open, thereby facilitatingunidirectional adjustment/shortening of length L of suture 39 disposedbetween distal anchor 62 and proximal anchor 82. As seen in FIG. 10B,when force F₂ is applied to suture 39, gaps G₁ and G₂ close down uponsuture 39, thereby forming a friction lock that precludes an increase inlength L of suture 39.

Referring now to FIG. 11, an alternative three rod anchor assembly isdescribed. The unidirectionally adjustable anchors described hereinabovewith respect to FIGS. 7-10 all comprise rods disposed within a cylinderhaving openings for passage of a suture. The openings act to center thesuture with respect to the rods and can be used to alter magnitudes offorce applied during adjustment and friction locking, as discussedpreviously. However, such openings present a risk of tearing or cuttingthe suture as the suture slides through the openings.

As seen in FIG. 11, anchor assembly 90 comprises distal anchor 62 andproximal anchor 92. Unidirectionally adjustable proximal anchor 92comprises first flexible rod 94 a and second flexible rod 94 b, as wellas rigid rod 96, which is preferably larger in diameter than first andsecond rods 94. Flexible rods 94 are preferably fabricated from Nitinolor a polymer, while rigid rod 96 is preferably fabricated from stainlesssteel or a polymer. Alternative materials will be apparent to those ofskill in the art.

Anchor 92 further comprises first outer cylinder 98 a and second outercylinder 98 b, which are crimped to the ends of first and second rods94, and rigid rod 96. As an alternative to crimping, first and secondcylinders 98 may each comprise an end cap (not shown) to which the rodsare coupled. First and second cylinders 94 do not span a central portionof anchor 92. Flexible rods 94 are separated from one another by gap G₁,while rods 94 are separated from rigid rod 96 by gap G₂.

Anchor 92 comprises three rods, but, unlike anchor 82 of FIG. 10, suture39 is only wrapped around two of them to achieve unidirectionaladjustment. As best seen in FIGS. 11B and 11C, the illustrative suturewinding of anchor assembly 90 is similar to that described previouslywith respect to anchor assembly 60 of FIGS. 7 and 8. The break betweenfirst and second cylinders 98 acts to center suture 39 with respect tothe rods, as seen in FIG. 11A, while rigid rod 96 acts to stiffen andreduce rotation of anchor 92 as it directs suture 39 about flexible rods94.

Suture 39 passes from distal anchor 62 to proximal anchor 92, betweenrigid rod 96 and flexible rods 94, around second flexible rod 94 b,around first flexible rod 94 a, between rigid rod 96 and first flexiblerod 94 a, between flexible rods 94 a and 94 b, and out. As seen in FIG.11A, when force F₁ is applied to suture 39, flexible rods 94 are forcedapart and gap G₁ widens while gap G₂ remains substantially constant,thereby allowing unidirectional adjustment of length L of suture 39disposed between distal anchor 62 and proximal anchor 92. As seen inFIG. 11B, when force F₂ is applied to suture 39, gap G₁ closes down uponsuture 39, thereby forming a friction lock that precludes an increase inlength L of suture 39. Gap G₂ again remains substantially constant.

With reference to FIG. 12, an alternative unidirectionally adjustableanchor assembly comprising pivots is described. Anchor assembly 100comprises distal anchor 62 and proximal anchor 102. Unidirectionallyadjustable proximal anchor 102 comprises outer cylinder 103 having firstend 104 a and second end 104 b (not shown), as well as first opening 105a and second opening 105 b. First and second openings 105 are preferablydisposed near the center of cylinder 103 and approximately 180° apart.Anchor 102 further comprises first rod or paddle 106 a and second rod orpaddle 106 b, both of which are disposed within outer cylinder 103 andcoupled to the first and second ends of cylinder 103 by pins 107, whichpass through pivot holes 108. In this manner, first and second paddles106 are able to rotate about pivot holes 108. Paddles 106 may be formed,for example, from stainless steel or a polymer, and are separated fromone another by gap G. As with the previous anchor assemblies, theprecise shape, size and materials of the anchors, as well as suture 39,may vary as required for specific applications.

Suture 39 illustratively passes from distal anchor 62 through firstopening 105 a of proximal anchor 102, around second paddle 106 b, aroundfirst paddle 106 a, between paddles 106 a and 106 b, and out throughsecond opening 105 b. The placement of pivot holes 108 ensures thatapplication of force F₁, as described hereinabove, causes paddles 106 torotate apart from one another and expand gap G, thereby enablingunidirectional adjustment. Likewise, application of previously discussedforce F₂ causes paddles 106 to rotate together, thereby closing gap Gand pinching suture 39 between the paddles in a friction lock. Anincrease in the magnitude of force F₂ serves to rotate paddles 106together more tightly, thereby increasing the magnitude of the frictionlock acting upon suture 39 between the paddles. In this manner,unidirectional adjustment is achieved.

Referring now to FIG. 13, an alternative unidirectionally adjustableanchor assembly comprising spring material is described. Anchor assembly110 comprises distal anchor 62 and proximal anchor 112. Unidirectionallyadjustable proximal anchor 112 comprises outer cylinder 113 having firstend 114 a and second end 114 b (not shown), as well as first opening 115a and second opening 115 b. First and second openings 115 are preferablydisposed near the center of cylinder 113 and approximately 180° apart.Anchor 112 further comprises first rod 116 a and second rod 116 b thatare separated by gap G, as well as spring material 118, all of which aredisposed within outer cylinder 113. Spring material 118 abuts rods 116,which preferably are substantially the same length as cylinder 113, andmay either move freely within cylinder 113 or may be coupled to the ends(not shown) of cylinder 113. Spring material 118 may also move freelywithin cylinder 113 or may be coupled to the cylinder, and compriseslumen 119 having a diameter that is preferably equal to or less than thediameter of suture 39. Spring material 118 may comprise, for example, acompressible biocompatible foam, which acts as a compression spring.

Suture 39 passes from distal anchor 62 to proximal anchor 112 throughfirst opening 115 a of cylinder 113, between rods 116, through lumen 119of spring material 118, and out through second opening 115 b. Lumen 119snugly contacts suture 39 such that application of force F₁ causesfriction between the suture and the spring material to compress thespring material against the wall of cylinder 114, thereby reducing astress applied to rods 116 by spring material 118 and increasing gap Gsuch that unidirectional adjustment of length L of suture 39 disposedbetween distal anchor 62 and proximal anchor 102 may proceed.Application of force F₂ stretches spring material 118 against rods 116,thereby increasing the stress applied to the rods by the spring materialand closing gap G such that suture 39 is friction locked between rods116.

With reference to FIG. 14, alternative unidirectionally adjustableanchor assemblies comprising one-way valves are described. In FIG. 14A,anchor assembly 120 comprises distal anchor 62 and proximal anchor 122.Unidirectionally adjustable proximal anchor 122 comprises outer cylinder124 having first and second ends 125 a and 125 b, as well as firstopening 126 a and second opening 126 b. First and second openings 126are preferably disposed near the center of cylinder 124 andapproximately 180° apart. Anchor 122 further comprises first inclinedplane 128 a and second inclined plane 128 b, which are forced intoapposition by compression springs 129 a and 129 b, thereby formingone-way valve V at the junction of the two inclined planes. Inclinedplanes 128 and springs 129 are disposed within outer cylinder 124;springs 129 abut ends 125 of cylinder 124, as well as the ends of theinclined planes. Suture 39′ comprises a plurality of knots or beads Badapted to actuate one-way valve V.

Suture 39′ passes from distal anchor 62 to proximal anchor 122 throughfirst opening 126 a of cylinder 124, between inclined planes 128,through one-way valve V, and out through second opening 126 b.Application of force F₁ to suture 39′ causes a bead B to contactinclined planes 128 and gradually coax them apart by compressing springs129, thereby opening valve V and allowing the bead to pass through thevalve. Once the bead has passed through valve V, springs 129 forceinclined planes 128 back into apposition, thereby closing the valve.Continued application of force F₁ allows multiple beads to pass throughthe valve, which facilitates unidirectional adjustment of suture lengthL disposed between distal anchor 62 and proximal anchor 122. Applicationof force F₂ causes a bead B of suture 39′ to impinge upon the proximalsides of inclined planes 128. However, force transferred to the planesby the bead is perpendicular to the direction required to compresssprings 129 and urge planes 128 apart. As such, the bead B impingingupon the proximal sides of planes 128 is not able to open one-way valveV and pass back through the valve in a distal direction, therebyensuring only unidirectional adjustment, i.e. shortening, of the lengthL of suture disposed between the proximal and distal anchors.

In FIG. 14B, an alternative unidirectionally adjustable anchor having aone-way valve is described. Anchor assembly 130 comprises distal anchor62 and proximal anchor 132. Unidirectionally adjustable proximal anchor132 comprises lumen 134 having cantilevered inclined plane 136 disposedtherein, which forms one-way valve V. ‘Zip-tie’ fastener 138, having aplurality of inclined planes 139, connects proximal anchor 132 anddistal anchor 62. The plurality of inclined planes 139 are disposedabout 180° out of phase with inclined plane 136 of anchor 132.

Fastener 138 passes from distal anchor 62 to proximal anchor 132,through lumen 134 and past inclined plane 136. Inclined planes 139 offastener 138 mesh with inclined plane 136 and bend or cantilever plane136, such that planes 139 of fastener 138 may proximally pass one-wayvalve V when force F₁ is applied to the fastener, thereby enablingunidirectional adjustment of length L of fastener 138 disposed betweenthe proximal and distal anchors. Conversely, when force F₂ is applied tothe fastener, the proximal side of inclined plane 136 of anchor 132abuts the distal side of an inclined plane 139 of fastener 138, and thefastener cannot be drawn distally through proximal anchor 132, nor canthe length L of fastener disposed between the anchors be increasedsignificantly.

Referring now to FIG. 15, alternative unidirectionally adjustable anchorassemblies comprising a slipknot are described. In FIG. 15A, anchorassembly 140 comprises distal anchor 142 and proximal anchor 144.Through-holes 143 a and 143 b extend through distal anchor 142, whilethrough-holes 145 a and 145 b extend through proximal anchor 145.Preferably, through-holes 143 and 145 are located near the center ofanchors 142 and 144, respectively.

The distal end of suture 39 passes through through-hole 145 a ofproximal anchor 144 to distal anchor 142, where it passes throughthrough-hole 143 a and back through through-hole 143 b. It then extendsfrom distal anchor 142 back to proximal anchor 144, where it passesthrough through-hole 145 b of the proximal anchor. The distal end ofsuture 39 is tied off at unidirectional slipknot S, which is locatedproximal of anchor 144. FIG. 15B provides a detail view illustratingformation of slipknot S.

As will be apparent to those of skill in the art, application of forceF₁ causes suture 39 to slide through through-holes 143 and 145, anddecrease the length L of suture 39 disposed between anchors 142 and 144.Suture 39 may readily pass through slipknot S in a proximal direction,thereby facilitating unidirectional adjustment of length L. However,application of force F₂ tightens slipknot S and prohibits passage ofsuture 39 through the slipknot in a distal direction, thereby precludingan increase in length L.

FIG. 15C illustrates an alternative embodiment of anchor assembly 140wherein the slipknot is disposed within the proximal anchor. Anchorassembly 140′ comprises distal anchor 142 and proximal anchor 144′.Proximal anchor 144′ comprises hollow cylinder or tube 146 having distalopenings 147 a and 147 b, and proximal opening 148.

The distal end of suture 39 passes through proximal opening 148 into theinterior of tube 146. It then passes through distal opening 147 a ofproximal anchor 144′ to distal anchor 142, where it passes throughthrough-hole 143 a and back through through-hole 143 b. Next, suture 39extends from distal anchor 142 back to proximal anchor 144′, where itpasses through distal opening 147 b into the interior of tube 146 of theproximal anchor. The distal end of suture 39 is tied off atunidirectional slipknot S, which is disposed within tube 146 of anchor144′. Anchor assembly 140′ may be unidirectionally adjusted in a mannersimilar to that described hereinabove with respect to anchor assembly140 of FIG. 15A.

FIGS. 7-15 illustrate anchor assemblies comprising various mechanismsfor achieving unidirectional adjustment of the distance between theproximal and distal anchors. These mechanisms have been provided solelyfor the sake of illustration and should in no way be construed aslimiting. Additional mechanisms for achieving unidirectional adjustmentwill be apparent to those of skill in the art in view of this disclosureand are included in the present invention. Furthermore, a majority ofthe anchor assemblies of FIGS. 7-15 have been described with the distalanchor being fixed relative to the suture, and the proximal anchor beingadjustable. However, it should be understood that the distal anchor mayalternatively be adjustable and the proximal anchor may be fixed, and/orboth anchors may be unidirectionally adjustable, as with anchor assembly140 of FIG. 15.

With reference now to FIG. 16, a bi-directionally adjustable anchorassembly comprising a locking mechanism is described. Anchor assembly150 comprises distal anchor 62 and proximal anchor 152. As seen in FIG.16A, bi-directionally adjustable proximal anchor 152 comprises outercylinder 153 having first end 154 a and second end 154 b, as well asfirst opening 155 a and second opening 155 b. First and second openings155 are preferably disposed near the center of cylinder 153 andapproximately 90° apart. Proximal anchor 152 further comprises tensionspring 158 disposed within outer cylinder 153.

As seen in FIG. 16B, suture 39 passes from distal anchor 62 to proximalanchor 152 through first opening 155 a, around spring 158, and outthrough second opening 155 b. Suture 39 moves freely about tensionspring 158 in either direction during application of force F₁ or forceF₂, thereby facilitating bi-directional adjustment of suture length Ldisposed between the proximal and distal anchors. However, as seen inFIG. 16C, simultaneous application of forces F₁ and F₂ with sufficientmagnitude causes suture 39 to force threads T of spring 158 apart, suchthat suture 39 is trapped between threads T and locked in position,thereby precluding further adjustment of suture length L.

The magnitude of forces required to actuate the locking mechanism ofproximal anchor 152 and lock suture 39 within threads T of spring 158may be specified/altered in a variety of ways. For example, the angularspacing of openings 155 about outer cylinder 153 may be altered, thespring constant of spring 158 may be specified, and/or spring 158 orsuture 39 may comprise a lubricious coating. Additional techniques willbe apparent to those of skill in the art. It is expected thatsimultaneous application of forces F₁ and F₂ will be encountered whenanchor assembly 150 has been deployed across a tissue fold and suturelength L has been adjusted such that the tissue fold is compressed. Amedical practitioner would then apply force F₁, while the compressedtissue fold would apply force F₂.

Although the anchor assemblies of FIGS. 10-16 have illustratively beendescribed without knots or loops of suture or fastener disposed proximalof the proximal anchor (as seen, for example, with knot 69 on suture 39of anchor assembly 60 in FIGS. 7 and 8) it should be understood thatsuch loops or knots optionally may be provided in order to facilitatedeployment and/or adjustment of the anchor assemblies. Additionally, thepreviously described anchor assemblies illustratively comprise distalrod- or T-type anchors. However, it should be understood that distalT-anchors have only been provided for the sake of illustration. Thedistal anchors (as well as the proximal anchors) may comprise any of avariety of anchors, per se known. Exemplary anchors are described inco-pending U.S. patent application Ser. No. 10/612,170, filed Jul. 1,2003, which is incorporated herein by reference in its entirety.Additional anchors are described hereinbelow with respect to FIG. 17.

Referring to FIG. 17A, articulating anchor 160 includes semi-cylindricalbase 161, rod 162 and suture 39. Rod 162 rotates about pivot point 163(as indicated by arrow 164) between an expanded position (shown in FIG.7A) and a reduced profile position, wherein rod 162 pivots within thesemi-cylindrical base 161. Articulating anchor 160 may be deliveredthrough a tissue fold using needle 34 described hereinabove with respectto FIG. 3E. Preferably, articulating anchor 160 is biased in theexpanded position so that it automatically expands once it is ejectedfrom the needle.

With respect to FIGS. 17B and 17C the anchors of the present inventionalso may comprise one or more oblong bodies connected by at least onesuture. In FIG. 17B, anchor 165 comprises elliptical ring 166 havingsutures 39 attached at substantially opposite sides of the ring. In FIG.17C, anchor 168 comprises angle bracket 169 having a pair ofthrough-holes 170 for suture 39. In FIG. 17D, anchor 171 comprisesoblong bead 172 having a pair of through-holes 173 for suture 39. Allthree anchors 165, 168 and 171 (as well as the T-anchors describedpreviously) have a first dimension (e.g., width) that is substantiallylarger than a second dimension (e.g., height). This dimensionaldifference necessitates that anchors 165, 168 and 171 be inserted withinneedle (e.g., needle 34 of FIG. 3E) in a particular orientation. Oncethe anchor is ejected through a tissue wall, tension on suture 39 forcesthe anchor to rotate so that it cannot be pulled back through the tissuewall. As will be understood by those of skill in the art, numerous otheranchors may be employed without departing from the scope of the presentinvention.

Referring now to FIG. 18A, an alternative embodiment of apparatus forforming a tissue fold, constructed in accordance with the principles ofthe present invention, is described. Apparatus 175 comprises treadmillassembly 176 disposed at distal tip 174 of flexible tube 177. Flexibletube 177 is configured to be inserted through a patient's mouth,esophagus and into the stomach. Treadmill assembly 176 comprisesconveyor 180 that circles around a pair of hubs 181 a and 181 b. Hubs181 a and 181 b rotate about axles 182 a and 182 b, respectively, andare interconnected by bracket 183. A plurality of barbs or needles 185is disposed at substantially regular intervals around the circumferenceof conveyor 180.

Flexible tube 177 preferably includes a plurality of through-wall slots186 to enhance flexibility of the tube, yet maintain torqueability.Preferably, flexible tube 177 is made from stainless steel with anetched or laser-cut slot pattern. Preferably, the slot pattern is asinusoidal repeating pattern of slots perpendicular to the longitudinalaxis of the tube.

Referring to FIGS. 18 and 19, transmission of motive force to treadmillassembly 176 is described. In particular, drive shaft 202 disposedwithin flexible tube 177 is coupled to a manual knob or motor located atthe proximal end of the catheter. The distal tip of drive shaft 202 isprovided with beveled gear 203 that meshes with beveled gear 204provided on axle 182 b. Accordingly, rotation of beveled gear 203 istransmitted to beveled gear 204, thereby causing axle 182 b to rotate.Axle 182 b in turn rotates hub 181 b, actuating conveyor 180. Reversingthe rotation of drive shaft 202 reverses the direction of conveyor 180.

Referring again to FIGS. 18A-18D, a method of forming a gastrointestinaltissue fold F using apparatus 175 is described. In FIG. 18A, flexibletube 177 is positioned transesophageally so that treadmill assembly 176contacts tissue wall W. Preferably, contact should be made at an anglerelative to the tissue wall W. For example, an angle of approximately 45degrees is depicted in FIG. 8A, while many other angles may be usedwithout departing from the scope of the present invention.

When treadmill assembly 176 contacts tissue wall W, needle 185 engagesthe tissue at contact point P1 as the needle moves around distal hub 181a. As depicted in FIG. 18B, as the needle moves away from distal hub 181a, tissue wall W is pulled towards proximal end 181 b, thereby forming asmall tissue fold F. As the treadmill assembly continues to turn,subsequent needles 185 engage the tissue wall so that it becomessecurely engaged to treadmill assembly 176 along the length of conveyor180.

As depicted in FIG. 18C, once tissue wall W is securely engaged totreadmill assembly 176, distal end 174 of flexible tube 177 may bearticulated in bendable section 190, thereby moving treadmill assembly176 away from tissue wall W. The articulation of flexible tube 177 maybe accomplished using a control wire and actuator disposed at theproximal end of the catheter, as previously described with respect tothe embodiment of FIG. 1. By moving the treadmill assembly away fromtissue wall W, additional tissue is pulled proximally and tissue fold Fbecomes elongated.

In FIG. 18D, tissue fold F is stretched across bendable section 190 offlexible tube 177 to create contact point P2. This permits a sharpenedneedle or obturator to be extended through one of slots 186 of bendablesection 190 and across all four layers of the tissue wall W.Advantageously, stretching of tissue fold F across bendable section 190permits an anchor to be ejected through both the muscularis and serosalayers, thus providing a durable foundation for gastrointestinal tissueapproximation. For example, needle 192 may be extended through slot 186in bendable section 190, and through the base of tissue fold F, and ananchor assembly (such as described with respect to any of FIGS. 4-17)may be ejected from needle 192 to secure the fold. Alternatively, anobturator (such as described with respect to FIGS. 5A and 5B) may beused to pierce the tissue fold at contact point P2 and deliver theanchor assembly. Treadmill assembly 176 may be disengaged from tissuewall W by reversing the rotation of proximal hub 181 b.

Referring now to FIG. 20A, a further alternative embodiment of apparatusfor forming a tissue fold in accordance with the principles of thepresent invention is described. Apparatus 200 comprises tissue grabbingassembly 18′ coupled to the distal end of a flexible tube 177′, such asdescribed with respect to the embodiment of FIG. 18. Flexible tube 177′preferably includes a plurality of through-wall slots 186′ to enhanceflexibility of the tube, yet maintain torqueability. In addition,flexible tube 177′ may be made from stainless steel with an etched orlaser-cut slot pattern, such as a sinusoidal repeating pattern of slotsperpendicular to the longitudinal axis of the tube.

Tissue grabbing assembly 18′ is similar to that described with respectto the embodiment of FIG. 1, and comprises a pair of jaws 28 a′, 28 b′arranged to rotate about pivot point 29′ between an open configurationand a closed configuration. Each of jaws 28 a′, 28 b′ preferablyincludes sharpened teeth 33′ disposed near its distal end to facilitategrasping tissue wall W.

With respect to FIG. 20A, tissue grabbing assembly 18′ is positionedtransesophageally adjacent to tissue wall W and jaws 28 a′, 28 b′ aremoved to the open position. Tissue grabbing assembly 18′ then is movedinto contact with tissue wall W. As depicted in FIG. 20B, tissuegrabbing assembly 18′ is used to grab the tissue wall at a first contactpoint P1. After capturing a portion of tissue wall W within jaws 28 a′,28 b′, flexible tube 177′ is urged proximally to stretch tissue wall Wand create tissue fold F.

Referring to FIG. 20C, once tissue fold F is formed, the distal end offlexible tube 177′ is articulated about bendable section 190′ to movetissue grabbing assembly 18′ away from tissue wall W. Articulation offlexible tube 177′ may be controlled using an actuator disposed at theproximal end of the catheter, thus causing tissue fold F to becomeelongated.

In FIG. 20D, tissue fold F is shown stretched across bendable section190′ so that a sharpened needle or obturator may be extended from one ofslots 186′ in bendable section 190′ and across all four layers of thetissue wall W. Needle 192′ then may be extended from slot 186′ inbendable section 190′ through contact point P2 and tissue fold F. Ananchor assembly (e.g., as described with respect to any of FIGS. 4-17)then may be ejected from needle 192′ to secure the fold. Alternatively,an obturator (e.g., as described with respect to FIGS. 5A and 5B) may beused to pierce the tissue fold at contact point P2 and deliver theanchor assembly.

With reference now to FIG. 21, an anchor delivery system adapted for usewith the adjustable anchor assemblies of FIGS. 7-17 is described. InFIG. 21, the anchor delivery system is illustratively shown in use withanchor assembly 60 of FIG. 7, but this should in no way be construed aslimiting. Also, the delivery system of FIG. 21 may be used inconjunction with apparatus for forming a tissue fold, such as apparatus10, 175 and 200 described previously, in order to anchor the tissuefold; or may be used for any other application, or in conjunction withany other apparatus, requiring delivery of an anchor assembly.

In FIG. 21A, a distal region of anchor delivery system 250 is disposedadjacent tissue fold F in tissue wall W. Anchor delivery system 250comprises flexible delivery tube 252 having lumen 253. Flexible deliverytube 252 may be configured for insertion through a patient's mouth andesophagus into a gastrointestinal lumen, such as the stomach. Lumen 253of delivery tube 252 preferably has a diameter of less than about 3 cm,and even more preferably has a diameter of about 2.5 cm. Flexibledelivery tube 252 preferably includes a plurality of through-wall slots254 to enhance flexibility of the tube, yet maintain torqueability.Slots 254 may form bendable section 255. Preferably, flexible deliverytube 252 is made from stainless steel with an etched or laser-cut slotpattern. The slot pattern is preferably a sinusoidal repeating patternof slots perpendicular to the longitudinal axis of the tube.

Anchor delivery system 250 further comprises delivery needle 260. Needle260 preferably has a length of less than 2 cm, and even more preferablyhas a length of about 1.5 cm. Needle 260 preferably comprises sharpeneddistal tip 262, lumen 264, slot 266 extending proximally from distal tip262, and proximal eyelet 268.

Lumen 264 of needle 260 is dimensioned such that a distal anchor may bedisposed therein. As discussed previously, anchor delivery system 250 isillustratively described in conjunction with anchor assembly 60 of FIG.7. In FIG. 21A, distal anchor 62 is disposed within lumen 264 of needle260. Suture 39 passes through slot 266 of the needle as the sutureextends from distal anchor 62 to proximal anchor 64. Needle 260preferably is disposed within lumen 253 of flexible delivery tube 252distal of bendable section 255, while proximal anchor 64 preferably isdisposed within delivery tube 252 proximal of bendable section 255.

In this arrangement, distal anchor 62 may be deployed through needle 260while the bendable section is actuated or bent, e.g., when anchordelivery system 250 is used in conjunction with previously describedplication apparatus. Proximal anchor 64 subsequently may be advancedthrough bendable section 255 after the bendable section has once againbeen straightened. The distance, or length, of suture 39 extendingbetween distal anchor 62, which is disposed distal of the bendablesection, and proximal anchor 64, which is disposed proximal of thebendable section, is preferably greater than or equal to about 2 cm, andis even more preferably greater than or equal to about 4 cm.

Needle 260 is proximally coupled to needle pushrod 270, whichfacilitates translation of the needle beyond a distal end of flexibledelivery tube 252. Needle pushrod 270 extends to a control actuatordisposed at a proximal end of anchor delivery system 250 (not shown).Pushrod 270 optionally may be spring-loaded (not shown), for example, tofacilitate puncture of tissue wall W and passage of needle 260 throughtissue fold F.

Anchor delivery system 250 further comprises anchor pushrod 280, whichis removably disposed through eyelet 268 of needle 260, and isconfigured to eject distal anchor 62 from lumen 264 of needle 260. Aswith needle pushrod 270, anchor pushrod 280 extends to a controlactuator disposed at a proximal end of anchor delivery system 250 (notshown). The actuators controlling pushrods 270 and 280 are preferably atleast partially coupled so that relative motion between the two pushrodscan be limited and/or eliminated, as needed. Pushrod 280 passes throughthe proximal loop of suture formed by knot 69 on suture 39, such thatthe suture loop is threaded between needle pushrod 270 and anchorpushrod 280. This facilitates unidirectional adjustment of the length ofsuture disposed between distal anchor 62 and proximal anchor 64, asdescribed hereinbelow.

In FIG. 21B, pushrods 270 and 280 are simultaneously distally advancedwith sufficient force, e.g., via spring-loading, such that sharpeneddistal tip 262 of needle 260 pierces tissue wall W and is advancedacross fold F. Bendable section 255 of flexible delivery tube 252optionally may be bent during advancement of the needle, as describedpreviously with respect to the plication apparatus (see FIG. 3E). Anchorpushrod 280 is then advanced distally with respect to needle pushrod 270and needle 260, such that it abuts distal anchor 62 and ejects theanchor from lumen 264 of needle 260 on the distal side of tissue fold F,as seen in FIG. 21C. Suture 39 likewise is ejected from slot 266 anddisposed across fold F.

During delivery, the longitudinal axis of distal anchor 62 issubstantially parallel to the longitudinal axis of needle 260. However,once anchor 62 has been ejected from needle 260, suture tension inducesthe anchor to rotate approximately 90° about its longitudinal axis, sothat its longitudinal axis is substantially perpendicular to thelongitudinal axis of needle 260. This rotation of distal anchor 62prevents it from being pulled back through tissue wall W. One or bothends of anchor 62 may be flared outward (not shown) to facilitate suchrotation upon contact with the tissue wall.

In FIG. 21D, anchor pushrod 280 is retracted proximally within lumen 264of needle 260, the needle is retracted within flexibly delivery tube 252via pushrod 270, and then delivery system 250 is retracted proximallyacross tissue fold F. Distal anchor 62 is disposed on the distal side ofthe tissue fold, suture 39 extends through the fold, and proximal anchor64 is disposed on the proximal side of the fold within delivery tube252. If bendable section 255 were flexed during deployment of distalanchor 62 (see FIG. 3E), it is straightened to facilitate delivery ofthe proximal anchor.

Delivery tube 252 is then retracted proximally with respect to pushrods270 and 280, causing needle 260 to exit lumen 253 of the delivery tubeon the proximal side of tissue fold F, thereby providing space forproximal anchor 64 to exit the lumen. Next, delivery tube 252 or thefull delivery system 250 is retracted, such that proximal anchor 64 isejected from delivery tube lumen 253, as seen in FIG. 21E. Delivery tube252 is then re-advanced and/or pushrods 270 and 280 are simultaneouslyretracted, such that needle 260 is repositioned within lumen 253 of thedelivery tube.

Flexible delivery tube 252 is advanced with respect to needle 260, suchthat it pushes proximal anchor 64 distally. The proximal suture loopformed by knot 69 on suture 39 catches against the proximal end ofneedle 260 and anchor pushrod 280, which pulls distal anchor 62 tautagainst tissue fold F, as seen in FIG. 21F. Continued advancement ofdelivery tube 252 unidirectionally adjusts, i.e. shortens, length L ofsuture 39 disposed between distal anchor 62 and proximal anchor 64,while forcing proximal anchor 64 against the tissue fold and firmlyanchoring the fold between the proximal and distal anchors.

Once length L has been adjusted such that anchor assembly 60 firmlyanchors tissue fold F in position, anchor pushrod 280 may be retractedproximally with respect to needle pushrod 270 and needle 260, such thatthe distal end of anchor pushrod 280 is proximally retracted througheyelet 268 and out of needle 260. As seen in FIG. 21G, the suture loopformed by knot 69 on suture 39 slips off the distal end of anchorpushrod 280, removing anchor assembly 60 from anchor delivery system 250and allowing the anchor delivery system to be removed from the patient.

Delivery system 250 optionally may comprise cutting apparatus (notshown) for removing the portion of suture extending proximally ofproximal anchor 64 post-adjustment. Alternatively, secondary apparatusmay be provided to remove such proximal length of suture. As yet anotheralternative, the unneeded length of suture may be left within thepatient post-procedure.

In order to decrease the number of steps required to deliver and adjustanchor assembly 60, once distal anchor 62 has been deployed, as in FIG.21C, the entire anchor delivery system 250 may be retracted proximally,such that needle 260 is retracted across tissue fold F while stilldisposed outside of delivery tube lumen 253. This is in contrast to themethod described with respect to FIG. 21D, wherein the needle isdisposed within the delivery tube prior to retraction across the tissuefold. Continued proximal retraction of anchor delivery system 250 ordelivery tube 252 deploys proximal anchor 64 from delivery tube lumen253. Anchor assembly 60 then may be unidirectionally adjusted, asdescribed previously.

As will be apparent to those of skill in the art, when anchor deliverysystem 250 is used in conjunction with previously described apparatus10, 175 or 200, to place an anchor assembly across fold F formed by saidapparatus, flexible delivery tube 252 may either comprise or be advancedthrough flexible tube 14, 177 or 177′, of apparatus 10, 175 or 200,respectively. Likewise needle 260 may comprise needle 34, 92 or 92′, ofapparatus 10, 175 or 200, respectively. Needle 260 may alternativelycomprise obturator 50 of FIG. 5.

Referring now to FIG. 22, an alternative anchor delivery system isdescribed. As with anchor delivery system 250 of FIG. 21, anchordelivery system 300 of FIG. 22 is adapted for use with the adjustableanchor assemblies of FIGS. 7-17. In FIG. 22, the anchor delivery system300 is illustratively shown in use with anchor assembly 60 of FIG. 7,but this should in no way be construed as limiting. Also, deliverysystem 300 may be used in conjunction with apparatus for forming atissue fold, such as apparatus 10, 175 and 200 described previously, inorder to anchor the tissue fold; or may be used for any otherapplication, or in conjunction with any other apparatus, requiringdelivery of an anchor assembly.

FIG. 22A illustrates a distal region of anchor delivery system 300.System 300 comprises flexible delivery tube 302 having lumen 303.Flexible delivery tube 302 may be configured for insertion through apatient's mouth and esophagus into a gastrointestinal lumen, such as thestomach. Flexible delivery tube 302 preferably includes a plurality ofthrough-wall slots 304 to enhance flexibility of the tube, yet maintaintorqueability. Slots 304 may form bendable section 305. Preferably,flexible delivery tube 302 is made from stainless steel with an etchedor laser-cut slot pattern. The slot pattern is preferably a sinusoidalrepeating pattern of slots perpendicular to the longitudinal axis of thetube.

Flexible delivery tube 302 further comprises end region 306, which iscoupled to anchor tube 307 having lumen or bore 308. As best seen inFIG. 22B, lumen 308 of anchor tube 307 communicates with lumen 303 ofdelivery tube 302 via through-slot 309. Proximal anchor 64 is disposedwithin anchor tube 307, while distal anchor 62 is disposed within needle260′, which sits within delivery tube 302.

Suture 39 passes out of needle 260′ from distal anchor 62 through slot266′. It then crosses from flexible delivery tube 302 to anchor tube 307via through-slot 309. After passing through proximal anchor 64, suture39 is passed back to delivery tube 302 via the through-slot, and isthreaded around anchor pushrod 280′, such that the loop of suture formedby knot 69 on suture 39 is disposed between needle pushrod 270′ andanchor pushrod 280′.

Needle 260′, needle pushrod 270′ and anchor pushrod 280′ aresubstantially the same as needle 260 and pushrods 270 and 280,respectively, which are described hereinabove with respect to anchordelivery system 250 of FIG. 21. Furthermore, anchor assembly 60 may bedelivered from and adjusted by anchor delivery system 300 in a mannersimilar to that described hereinabove with respect to system 250.

In FIG. 22A, anchor tube 307 of anchor delivery system 300 isillustratively shown as a relatively short tube having lumen or bore 308adapted for disposal of proximal anchor 64 therein. However, it shouldbe understood that anchor tube 307, lumen 308 and/or through-slot 309alternatively may extend all or part of the way to a proximal end offlexible delivery tube 302 of delivery system 300. Advantageously, suchan arrangement facilitates loading of anchor assembly 60 from a proximalend of the anchor delivery system and may simplify manufacturing of thesystem.

Anchor delivery system 300 illustratively has been described with asingle anchor assembly 60 disposed therein. However, it should beunderstood that a plurality of anchor assemblies may be loaded withindelivery system 300, thereby facilitating delivery of multiple anchorassemblies across different points of a tissue fold, across different(e.g., adjacent) tissue folds, or across other tissue structures. Theplurality of distal anchors 62 preferably are loaded within needle 262′of flexible delivery tube 302, while the plurality of proximal anchors64 preferably are loaded within lumen 308 of anchor tube 307.

An advantage of anchor delivery system 300, as compared to system 250 ofFIG. 21, is that both the proximal and distal anchors are located distalof the bendable section of the delivery tube during delivery. Thisreduces an initial length of suture that must be disposed between theanchors, thereby reducing a length of unneeded suture extendingproximally of the proximal anchor post-delivery and adjustment. It alsosimplifies delivery by allowing both the proximal and distal anchors tobe delivered while the bendable section of the delivery tube is bent.Additionally, placement of the proximal anchor in a separate anchor tubeeliminates a need to eject the needle from the flexible delivery tube onthe proximal side of a tissue fold in order to deploy the proximalanchor, thereby reducing a risk of accidental tissue puncture with theneedle.

With reference to FIG. 23, another alternative anchor delivery system isdescribed. As with anchor delivery systems 250 and 300 of FIGS. 21 and22, respectively, anchor delivery system 400 of FIG. 23 is adapted foruse with the adjustable anchor assemblies of FIGS. 7-17. Anchor deliverysystem 400 is illustratively shown in use with anchor assembly 60 ofFIG. 7, but this should in no way be construed as limiting. Also,delivery system 400 may be used in conjunction with apparatus forforming a tissue fold, such as apparatus 10, 175 and 200 describedpreviously, in order to anchor the tissue fold; or may be used for anyother application, or in conjunction with any other apparatus, requiringdelivery of an anchor assembly.

FIG. 23 illustrates a distal region of anchor delivery system 400.System 400 comprises flexible delivery tube 402 having lumen 403.Flexible delivery tube 402 may be configured for insertion through apatient's mouth and esophagus into a gastrointestinal lumen, such as thestomach. Flexible delivery tube 402 preferably includes a plurality ofthrough-wall slots to enhance flexibility of the tube, yet maintaintorqueability. The slots may form bendable section 405.

Anchor delivery system 400 further comprises delivery needle 260″, whichis disposed within lumen 403 of flexible delivery tube 402 distal ofbendable section 405 during delivery. As discussed previously, anchordelivery system 400 is illustratively described in conjunction withanchor assembly 60 of FIG. 7. Needle 260″ preferably has a lengthsufficient for both distal anchor 62 and proximal anchor 64 of anchorassembly 60 to be disposed therein; for example, needle 260″ preferablyhas a length of less than about 5 cm, and even more preferably has alength of about 3 cm. Except for an increase in length, needle 260″ issubstantially the same as needle 260 of FIG. 21.

In FIG. 23, both distal anchor 62 and proximal anchor 64 are disposedwithin lumen 264″ of needle 260″. Suture 39 passes through and backthrough slot 266″ of the needle as the suture extends from distal anchor62 to proximal anchor 64. Alternatively the length of suture between theproximal and distal anchors may be disposed within the needle duringdelivery. Advantageously, both the proximal and distal anchors of anchorassembly 60 may be deployed through needle 260″ while bendable section405 is actuated or bent, e.g., while anchor delivery system 400 is usedin conjunction with previously described plication apparatus.

Needle 260″ is proximally coupled to flexible needle pushtube 420, whichfacilitates translation of the needle beyond a distal end of flexibledelivery tube 402. As will be apparent to those of skill in the art,needle 260″ and needle pushtube 420 optionally may be manufactured as asingle piece. Needle pushtube 420 comprises lumen 422, as well as skive424 that communicates with lumen 422. Needle pushtube 420 extends to acontrol actuator (not shown), which may be spring-loaded, disposed at aproximal end of anchor delivery system 400.

Anchor pushrod 280″, which is substantially the same as anchor pushrod280 described previously, is removably disposed within lumen 422 ofneedle pushtube 420 distal of skive 424. As with pushtube 420, anchorpushrod 280″ extends to a control actuator (not shown) disposed at aproximal end of the anchor delivery system. Suture 39 proximally extendsfrom proximal anchor 64 through slot 266″ of needle 260″, through skive424 and within lumen 422 of needle pushtube 420, around anchor pushrod280″ and out through skive 424 to knot 69. The proximal loop of sutureformed by knot 69 is trapped around pushrod 280″ and within lumen 422 ofthe needle pushtube, thereby facilitating unidirectional adjustment ofthe length of suture disposed between distal anchor 62 and proximalanchor 64. As an alternative to the proximal loop of suture, knot 69 maybe formed on the proximal end of suture 39, such that the knot istrapped between anchor pushtube 280″ and needle pushrod 420 (see knot Kof FIG. 24).

Anchor assembly 60 may be delivered from and adjusted by anchor deliverysystem 400 in a manner similar to that described hereinabove withrespect to system 250 of FIG. 21, with a few alterations. Specifically,during deployment of distal anchor 62, anchor pushrod 280″ is advancedagainst proximal anchor 64, which in turn advances in-line distal anchor62. The pushrod is advanced a sufficient distance with respect to needle260″ to eject the distal anchor from needle lumen 264″, but not so faras to also prematurely eject proximal anchor 64. Motion limitationapparatus may be provided to ensure that the distal anchor is notprematurely ejected. Exemplary motion limitation apparatus is describedhereinbelow with respect to FIG. 24; additional apparatus, per se known,will be apparent.

In order to eject proximal anchor 64 from lumen 264″ of needle 260″,either the needle is retracted until length L of suture 39 disposedbetween the proximal and distal anchors is pulled taut and pulls theproximal anchor out of the needle lumen, or anchor pushrod 280″ isadvanced a sufficient distance within the lumen of needle 260″ to ejectthe proximal anchor from the lumen (or a combination thereof).Additionally, in order to release anchor assembly 60 from anchordelivery system 400 post-delivery and adjustment, anchor pushrod 280″ isretracted proximal of skive 424 such that the loop of suture 39 formedby knot 69 is no longer trapped within lumen 422 of needle pushrod 420.

A significant advantage of anchor delivery system 400, as compared tosystem 250 of FIG. 21, is that both the proximal and distal anchors aredisposed distal of bendable section 405 of flexible delivery tube 402. Asignificant advantage of anchor delivery system 400, as compared tosystem 300 of FIG. 22, is that both the proximal and distal anchors aredisposed within needle 260″, thereby eliminating a need for an anchortube and reducing the profile of the system.

Referring now to FIG. 24, an alternative embodiment of anchor deliverysystem 400 is described comprising motion limitation apparatus. Anchordelivery system 400′ is substantially the same as system 400, exceptthat needle pushrod 420′ comprises two skives: motion limitation skive430 and unidirectional adjustment skive 432, both of which communicatewith lumen 422′ of the needle pushrod. Suture 39 proximally extends fromproximal anchor 64, through motion limitation skive 430 and within lumen422′ between anchor pushrod 280″ and needle pushtube 420′. Suture 39exits skive 430 and is tied off at motion limitation knot K, which istrapped at skive 430 by anchor pushrod 280″. Suture 39 then continuesproximally to unidirectional adjustment skive 432 and the proximal loopof suture formed by knot 69, which is trapped at skive 432 aroundpushrod 280″.

A length of suture extending between proximal anchor 64 and knot K isspecified such that distal anchor 62 may exit lumen 264″ of needle 260″,but proximal anchor 64 cannot while knot K is trapped at skive 430 byanchor pushrod 280″. For example, during delivery of anchor assembly 60across a tissue fold, advancement of pushrod 280″ advances proximalanchor 64, which in turn advances in-line distal anchor 62 until thedistal anchor is ejected from needle lumen 264″ on the distal side ofthe tissue fold. Knot K limits a distance anchor pushrod 280″ may beadvanced and ensures that proximal anchor 64 is not prematurelydeployed.

Once anchor delivery system 400′ is again disposed on the proximal sideof the tissue fold, anchor pushrod 280″ is retracted proximal of motionlimitation skive 430, thereby allowing knot K to escape from skive 430and facilitating deployment of proximal anchor 64. Proximal anchor 64may be deployed by either retracting needle 260″ until the length ofsuture between the two anchors is pulled taut and pulls the proximalanchor out of the needle, or by re-advancing pushrod 280″ to push theproximal anchor out of the needle.

The anchor assembly may then be unidirectionally adjusted via the sutureloop trapped at skive 232, as described previously. After adjustment hasbeen completed, anchor pushrod 280″ is retracted proximal ofunidirectional adjustment skive 432, thereby allowing the loop of sutureformed by knot 69 of suture 39 to escape from skive 432. A significantadvantage of anchor delivery system 400′, as compared to system 400 ofFIG. 23, is that motion limitation skive 430 reduces a risk of prematuredeployment of proximal anchor 64.

Although preferred illustrative embodiments of the present invention aredescribed hereinabove, it will be apparent to those skilled in the artthat various changes and modifications may be made thereto withoutdeparting from the invention. It is intended in the appended claims tocover all such changes and modifications that fall within the truespirit and scope of the invention.

1. Apparatus for securing a tissue fold within a patient, the apparatuscomprising: an elongate member having a proximal end and a distal end;application apparatus extending from the distal end of said elongatemember and having a distal portion adapted to engage a tissue foldwithin a patient; and an anchor assembly having proximal and distalanchors connected by a suture, said suture having a proximal end and adistal end, wherein the anchor assembly is adapted for adjustment of thelength of suture disposed between the proximal and distal anchors whilethe anchor assembly is disposed across the tissue fold; furthercomprising an anchor delivery system adapted to deploy and secure theanchor assembly across the tissue fold; wherein the anchor deliverysystem comprises a flexible delivery tube having a lumen, and a hollowneedle disposed within the lumen, said anchor delivery system having adistal region extending from the distal end of said elongate member;wherein the distal anchor passes through the hollow needle duringdelivery; wherein the anchor delivery system further comprises an anchortube coupled to a distal region of the flexible delivery tube, andwherein the proximal anchor is disposed within the anchor tube duringdelivery; wherein the anchor delivery system further comprises a trapmechanism located substantially within the distal region of said anchordelivery system, said trap mechanism being adapted to reversibly trapthe suture at or near its proximal end to facilitate adjustment of thelength of suture disposed between the proximal and distal anchors, andwherein the trap mechanism is adapted to release the suture after thelength of suture has been adjusted.
 2. Apparatus for securing a tissuefold within a patient, the apparatus comprising: an elongate memberhaving a proximal end and a distal end; application apparatus extendingfrom the distal end of said elongate member and having a distal regionadapted to engage a tissue fold within a patient; and an anchor assemblyhaving proximal and distal anchors connected by a suture, said suturehaving a proximal end and a distal end, wherein the anchor assembly isadapted for adjustment of the length of suture disposed between theproximal and distal anchors while the anchor assembly is disposed acrossthe tissue fold; further comprising an anchor delivery system adapted todeploy and secure the anchor assembly across the tissue fold; whereinthe anchor delivery system comprises a flexible delivery tube having alumen, and a hollow needle disposed within the lumen, said anchordelivery system having a distal region extending from the distal end ofsaid elongate member; wherein the anchor assembly passes through thehollow needle during delivery; wherein the anchor delivery systemfurther comprises a trap mechanism located substantially within thedistal region of said anchor delivery system, said trap mechanism beingadapted to reversibly trap the suture at or near its proximal end tofacilitate adjustment of the length of suture disposed between theproximal and distal anchors, and wherein the trap mechanism is adaptedto release the suture after the length of suture has been adjusted. 3.The apparatus of claim 2, further comprising an anchor pushrod incommunication with an interior of the needle, the anchor pushrod adaptedto eject the anchor assembly from the needle.